Hartlaub, 1909
Description
Umbrella rather flatter than hemisphere [Helgicirrha schulzei ], with moderately thick jelly. Velum 1/3 - 1/4 of bell radius. Stomach short, situated on narrow, elongate gastric peduncle extending well beyond umbrella margin [H.schulzei-male-habitus;H.schulzei-details figure A].
Mouth with four short upwardly curved lips with folded margins [H.schulzei-details figure B]. Radial canals four, extending from bell margin to end of peduncle; these and ring canal narrow. One adaxial subumbrellar excretory pore opposite each marginal tentacle base; rudimentary bulbs.
Gonads usually linear, limited to subumbrellar disc, usually extending along radial canals from near base of peduncle almost to ring canal, straight to sinuous, without median furrow [H.prolifer-male-habitus ].
Marginal tentacles of two kinds. Larger ones 30-40, with wide elongate conical bases, with or without lateral spiral cirri; smaller ones usually up to 100, sometimes more, each with one or a pair of lateral cirri [H.schulzei-details figure C]. Up to 50+ closed marginal vesicles each with 1-4 concretions.
Young specimen: H.schulzei-young-habitus.
Size
Diameter of fully grown umbrella ca 30-40 mm. Mature at diameter of 12-20 mm, with corresponding bell height 6-8 mm (Brinckmann-Voss, 1973).
Colour
Stomach, gonads and marginal tentacles colourless to delicate green or reddish brown, with fine deep indigo specks on umbrella margin and developing marginal bulbs.
Ecology
Off Plymouth, medusa were recorded from June to October and in December (peak evidently spanning late summer to autumn); off Trieste in all months except July and August (Russell, 1953a); Naples, reported mainly March-June but also October-February (Brinckmann-Voss, 1973); off Roscoff fertile medusae have been collected in September (Bouillon, 1971).
Depth range
Coastal plankton.
Distribution in the North Sea
German Bight to southern North Sea.
World distribution
Off mainland Europe recorded from N Jutland south to Roscoff (Russell, 1953a; Bouillon, 1971); and Portugal down to the Mediterranean Sea (Kramp, 1961) but only once in the eastern part just off N Israel (Schmidt, 1974). South to Congo (Kramp) and SW Africa (Pagès, 1991). Once in the Red Sea but not otherwise recorded from Indian Ocean (Schmidt, 1973).
[After Cornelius, 1995a]